An electrical junction box to be mounted on a motor vehicle or the like contains a printed board and wiring members, such as bus bars, connectors, and fuses so that they can keep a good maintenance function and can be arranged efficiently in the box. Recently, an electrical junction box including various kinds of controlling devices has been proposed. Such an electrical junction box is installed in a suitable space obtained in a passenger room or an engine room. In this case, there are some electrical junction boxes in which a separate bracket is attached to an outer peripheral wall portion of an electrical junction box body and an electrical junction box body is fixed and supported through the bracket on a vehicle body panel or the like. Even if a shape of the box body is different from that of a fixing position, it is possible to commonly use the electrical junction box body, by separating the bracket from the electrical junction box body.
Generally, an electrical junction box includes a hollow electrical junction box body formed by assembling a pair of casings. That is, one casing (inner casing) is superimposed on the other casing (outer casing) and an outer periphery of the one casing is covered with a peripheral wall portion of the other casing. As disclosed in Patent Document 1 (JP 2004-96899 A), the peripheral wall portion of the other casing is provided with an engagement lock portion. The bracket is attached to the engagement lock portion.
However, since the bracket is fixed on only the peripheral wall portion of the other casing of the electrical junction box body in the conventional electrical junction box disclosed in Patent Document 1, it was difficult to obtain a sufficient strength in a connecting part between the bracket and the box body. That is, when a great external force is applied to the electrical junction box, a load will be concentrated on the peripheral wall portion of the other casing to which the bracket is attached. Consequently, the peripheral wall portion of the other casing is likely to be deformed so that the peripheral wall portion is removed from the one casing and is bulged outward. The peripheral wall portion of the other casing is broken by the deformation, the bracket is loosened at the attaching portion on the electrical junction box body by the deformation, the assembling condition between the pair of casings constituting the electrical junction box body become unstable by the deformation, or internal circuits are affected by the deformation.
As disclosed in Patent Document 1, it may be considered to prevent the peripheral wall portion of the other casing from being lifted from the outer periphery of the one casing by locking the engagement projection portion protruding from the outer periphery of the one casing onto the peripheral wall portion of the other casing. However, this structure cannot obtain a sufficient strength, since the engagement projection portion is locked on the thin peripheral wall portion. In addition, the locking mechanism of the peripheral wall portion must dispose an engagement lock portion, on which the bracket is mounted, on a remote position. Accordingly, there is a problem that a space cannot be obtained in the case where a plurality of engagement lock portions are juxtaposed.
[Prior Technical Document]
[Patent Document]
[Patent Document 1] JP 2004-96899 A